Devices that provide depth data of a snow covered area are used for determining: i) water resources for spring run-off, ii) snow thickness for climate model, iii) depth during the building of snow roads, snow runways, or structural foundations on the snow, and iv) a vehicle's ability to move through snow. These snow depth data for a snow covered area is compiled from a large number of snow depth measurements along traverse lines ranging from 30 to 500 feet in length. Prior known devices include using a thin cylindrical probe with an attached measuring tape. This type of probe is first pushed into the snow, then an operator bends over and reads the tape value at the snow surface, and then hand records this reading in a field book. This device and method is slow and tedious, e.g. a 100 measurements typically requires over 30 minutes to perform, and over 20 minutes to enter this compiled data in a computer data base. Human errors are common during this manual data recording. Thus, a portable snow depth measurement device is needed that is faster and easier to use, as well as eliminating the need for manual data entry.
Another device that provides snow depth data is taught in U.S. Pat. No. 4,600,842 by Boshung et al. entitled "Snowfall Measuring Method & Apparatus." This teaching discloses a stationary device with a rack component alone with an attached probe that is raised and lowered towards a fixed reference ground plate for measurements of snow depth performed by the device's electronics package that includes an alarm and a processor component. However, this device is not adaptable for portable repositioning for measurements at varied locations as provided for by the instant invention.
The problems discussed above are resolved by the instant invention by use of a probe with a linear displacement magnetostrictive transducer for reliable snow depth measurements in combination with a data logger that automatically records these measurements, and that can readily be downloaded to another computer for data analysis or graphical presentation.